Packaged product and process for making same

ABSTRACT

A packaged product comprises a boneless food product comprising at least one member selected from the group consisting of meat and cheese. The food product has added liquid thereon, for example brine which has been injected into (and is exuding from) a meat product, or brine in which cheese has been soaking. The film article surrounds the boneless food product, and is in contact with both the boneless food product and the added liquid. The packaged product exhibits a Standard Drop Test failure rate of less than 60 percent. A packaging process involves placing the boneless food product into a packaging article, which may be a bag, pouch, or casing, the boneless food product having added liquid thereon. The added liquid on the surface of the meat product contaminates an inside surface of the packaging article which is to be sealed. The packaging article is then sealed across an open end thereof, the seal being made through the contamination on the inside surface of the meat product. The resulting packaged product exhibits a Standard Drop Test failure rate of less than 60 percent.

1. FIELD OF THE INVENTION

[0001] The present invention relates to a packaged product in which anarticle, such as a bag, pouch, or casing, is used to package a product,such as food. The invention also relates to a process for making thepackaged product according to the present invention.

2. BACKGROUND OF THE INVENTION

[0002] Injecting fresh meat with liquid, such as brine, is a means totenderize the meat. The brine interacts with the muscle proteins, withthe resulting liquid mixture exuding from the meat. During packaging,the liquid which is on the surface of such injected meat products is ablend of the injected brine, muscle proteins, and natural juices andblood from the meat product. This liquid blend tends to smear onto thepackaging film in the region to be sealed. The liquid blend is difficultto seal through. We have analyzed the seal strength of seals made underconditions of this type of contamination, and have discovered that thestrength of seals made through the liquid blend can be even more than80% less than the strength of seals made without the liquid blend beingpresent in the seal area while the seal is made.

[0003] While some processors have successfully solved this weak-sealproblem with equipment and line layouts which prevent contamination ofthe seal area with brine, other processors continue to have significantproblems. Moreover, it has been found that high-shrinking bagsexacerbate the seal failure problem. That is, as the bag shrinks, theseal contacts the product which puts pressure on the seal, which cancause seal failure as the seal shrinks tightly up against the product.

[0004] One solution to the seal failure problem has been to provide anoversized shrink bag, so that the seal is made far enough from theproduct that the shrinkage of the bag does not result in the sealcontacting the product within the bag. Although this may reduce the sealfailure problem, it causes other problems. More particularly, itproduces a packaged product of lesser aesthetic value due to excess filmextending outward from the product being packaged. Secondly, the excessfilm provides an envelope which tends to collect juices from the meatproduct, which are unsightly and also exhibit an accelerated spoilagerate relative to the remainder of the meat product. It would also bedesirable to avoid the seal failure problem while also avoiding theproblems of diminished aesthetic appearance due to excess film,unsightly juice accumulation in the envelope of the excess film, andreduced shelf life due to accelerated spoilage rates caused by the juicewhich accumulates in the envelope of the excess film. The inventors ofthe present invention have arrived at a solution to these problems.

SUMMARY OF THE INVENTION

[0005] We have discovered that seal failure rates can be dramaticallyreduced for the packaging of a boneless meat product in which the meathas been injected with brine, without using an oversized bag and whileproviding a package in which the film is shrunk tightly against the meatproduct. We have discovered that bags made from particular films can besealed through a brine-containing liquid blend, with significantly fewerseal failures even after the film is shrunk tightly against the bonelessmeat product. Moreover, it has been found that the use of lower shrinktension and/or lower free shrink can assist in reducing the seal failuredue to the seal pulling down tightly against the product being packagedduring shrinkage of the film after it is sealed around the product. Ourinvention enables us to package a product using a bag which is sizedcloser to the size of the product, thereby providing a final packagedproduct with an appearance which is of greater aesthetic appeal, i.e.,versus the use of an oversized bag.

[0006] Using a highly abusive test, we have assessed a seal failure rateof about 66 percent using bags which are currently in commercial use forthe packaging of brine-injected boneless pork products. However, throughthe use of bags made from films of particular polymers (especiallymetallocene-catalyzed ethylene/alpha-olefin copolymers in the seallayer), as well as by providing the film with a relatively low freeshrinkage (and/or substantially lesser shrink tension) in a directionwhich, in general, is perpendicular to the seal made through thecontamination, we have discovered that we can reduce the seal failurerate to a level as low as 26 percent, using the same highly abusivetest. This is a 60 percent reduction in seal failure rate, using a testwe believe to be significantly more abusive than the actual conditionsof use of the packaged products. In view of the substantial improvementin seal integrity during our highly abusive testing, we believe that incommercial use our packaged products will exhibit a seal failure ratewhich is a substantial improvement over the seal failure rate currentlybeing experienced in the commercial market.

[0007] As a first aspect, the present invention is directed to apackaged product comprising: (A) a boneless food product comprising atleast one member selected from the group consisting of meat and cheese,the food product having a free liquid additive thereon, and (B) a filmarticle which is both surrounding and in contact with both the foodproduct and the free liquid. The packaged product exhibits a StandardDrop Test failure rate of less than 60 percent; more preferably, lessthan 55 percent; still more preferably, less than 50 percent; yet stillmore preferably, less than 45 percent; still more preferably, less than40 percent; still more preferably, less than 35 percent; still morepreferably, less than 30 percent.

[0008] Preferably, the film article comprises a heat-shrinkable film.Preferably, the film is a multilayer film comprising a seal layercomprising a homogeneous ethylene/alpha-olefin copolymer. Preferably,the film has a thickness of from about 1.5 to 3 mils, more preferably,from about 1.8 to 2.7 mils; still more preferably, from about 2 to 2 4mils. Preferably, the film has a free shrink of from about 15 to 60percent in at least one direction; more preferably, from about 20 to 50percent. Preferably, the film has a shrink tension of from about 50 to350 pounds per square inch (i.e., “psi”) in a first direction, and fromabout 300-1000 in a second direction, more preferably, from about 100 to200 psi the first direction, and from about 360 to 600 psi in the seconddirection. Shrink tension is measured in accordance with ASTM D 2838,the entirety of which is hereby incorporated by reference thereto

[0009] If the film article is an end-seal bag, preferably the firstdirection is the machine direction (i e, longitudinal direction), sothat a seal made through liquid contamination is forced against theproduct by the shrink tension in the first direction. Likewise, if thefilm article is a side-seal bag, preferably the first direction is thetransverse direction. Preferably, the second direction has a shrinktension of at least about 120 percent of the shrink tension of the firstdirection, more preferably, from about 150 to 2000 percent of the shrinktension of the first direction, still more preferably, from about 150 to350 percent of the shrink tension of the first direction; and, yet stillmore preferably, from about 150 to 300 percent of the shrink tension ofthe second direction.

[0010] Preferably, the multilayer film has a seal layer comprising atleast one member selected from the group consisting of polyolefin,polyamide, polyester, polyvinyl chloride, and ionomer; more preferably,homogeneous ethylene/alpha-olefin copolymer, ethylene/unsaturated estercopolymer (especially ethylene/vinyl acetate copolymer), and ionomer.Preferably, the seal layer comprises homogeneous ethylene/alpha-olefincopolymer in an amount of at least about 90 weight percent. Aparticularly preferred seal layer comprises homogeneousethylene/alpha-olefin copolymer in an amount of about 80 percent, basedon layer weight, and linear low density polyethylene in an amount ofabout 20 percent, based on layer weight. Preferably, the multilayer filmfurther comprises an O₂-barrier layer, which in turn preferablycomprises at least one member selected from the group consisting ofethylene/vinyl alcohol copolymer, polyvinylidene chloride (PVDC),polyalkylene carbonate, polyamide, polyethylene naphthalate, polyester,polyacrylonitrile. Preferably, the film comprises a crosslinked polymernetwork, which is preferably obtained by irradiation of one or morelayers of the film. If the multilayer film comprises an O2-barrierlayer, preferably the film further comprises one or more adhesive layers(i.e., “tie” layers) to enhance interlayer adhesion of the various filmlayers to one another.

[0011] Preferably, the free liquid additive comprises brine. Preferably,the brine is present in an amount of from about 1 percent to 30 percent,based on the weight of the product; more preferably, from about 5 to 25percent; still more preferably, from about 6 to 20 percent; yet stillmore preferably, from about 10 to 12 percent, or from about 16 to 18percent. Preferably, the food product comprises meat. Preferably, themeat product comprises at least one member selected from the groupconsisting of poultry, pork, beef, lamb, goat, horse, and fish, morepreferably, at least one member selected from the group consisting ofpoultry, pork, beef, and lamb; still more preferably, at least onemember selected from the group consisting of pork and beef, yet stillmore preferably, brine-injected pork.

[0012] As a second aspect, the present invention is directed to apackaging process comprising: (A) making a packaging article having anopen top, (B) placing into the packaging article a boneless food producthaving an added liquid thereon, and (C) heat sealing across the open topof the packaging article. The packaging article comprises at least onemember selected from the group consisting of a bag, a pouch, and acasing. When being placed into the packaging article, the boneless foodproduct deposits liquid contamination onto a region of an inside surfaceof the packaging article before the packaging article is sealed acrossthe top thereof. The liquid contamination comprises the added liquid.Upon sealing across the top of the packaging article and through theliquid contamination, a packaged product is formed. The packaged productexhibits a Standard Drop Test failure rate of less than 60 percent.

[0013] Preferably, the process further comprises evacuating atmospherefrom within the packaging article after the boneless food product isplaced into the packaging article but before the heat sealing across theopen top of the packaging article. Preferred films, food products, andadded liquids are as set forth above in the first aspect of the presentinvention. Preferably, brine is injected into a boneless meat productbefore the meat product is placed into the packaging article.Preferably, the packaging article comprises at least one member selectedfrom the group consisting of an end-seal bag, a side-seal bag, a casing,and a pouch, with the first direction being parallel to a length of thearticle, and the second direction being perpendicular to the length ofthe article. If the first direction is a machine direction and thesecond direction is a transverse direction, preferably the article is anend-seal bag, casing, or pouch; if the first direction is the transversedirection and the second direction is the machine direction, preferablythe article is a side-seal bag. If the packaging article is a casing, itcan be either seamless or backseamed. If the packaging article is apouch, it can be an L-seal pouch or a U-seal pouch.

[0014] As a third aspect, the present invention is directed to apackaged product comprising a bone-in meat product having a free liquidadditive thereon, and a film article which is both surrounding and incontact with both the bone-in meat product and the free liquid. Thepackaged product exhibits a Standard Drop Test failure rate of less than30 percent. Preferred films are as described above in the first andsecond aspects of the present invention. Preferred boneless meatproducts include bone-in beef, pork, lamb, foul (including chicken,turkey, etc.), fish, goat, and horse

BRIEF DESCRIPTION OF THE DRAWINGS

[0015]FIG. 1 illustrates an end-seal bag in lay-flat view, the bag beinguseful in a packaged product according to the present invention.

[0016]FIG. 2 illustrates a cross-sectional view taken through section2-2 of FIG. 1.

[0017]FIG. 3 illustrates a side-seal bag in lay-flat view, the bag beinguseful in a packaged product according to the present invention.

[0018]FIG. 4 illustrates a cross-sectional view taken through section4-4 of FIG. 3.

[0019]FIG. 5 illustrates a schematic view of a preferred process formaking a multilayer film useful in the packaged product of the presentinvention.

DETAILED DESCRIPTION OF THE INVENTION

[0020] As used herein, the phrase “added liquid” refers to any liquidwhich is added to the food product, i.e., to the surface of the foodproduct and/or within the structure of the food product. Examples ofadded liquids include brine, spice solutions, etc., injected into meatproducts, or used as soaking solutions for cheese. Ultimately, a portionof the added liquid remains within the food product at the time ofpackaging, while another portion of the added liquid exudes onto thesurface (or remains on the surface) of the food product at the time ofpackaging. It is this added liquid which is on the surface of the foodproduct, i.e., not within the food product, which is available tocontaminate the inside surface of the packaging article which is to besealed. The added liquid which contaminates the inside surface of thepackaging article is responsible for the lowering of the strength of theresulting seal. In the present invention, brine is a preferred addedliquid. As used herein, the term “brine” is inclusive of a solution ofsalt (e.g sodium chloride) in water, regardless of whether or not othersalts are also present, such as various phosphate-containing salts.Preferably, the brine contains salt in an amount of from about 3 to 20percent, based on the weight of the solution.

[0021] As used herein, the phrase “free liquid” refers to liquid that isin a package which contains a food product, the liquid being in thepackage but not contained within the food product. That is, a freeliquid is not being held within the boneless-food product. For example,“purge”, which is known by those of skill in the art as being naturaljuice exuded from fresh meat, is considered to be a free liquid once theliquid exudes from the meat product. Moreover, liquid that is present onthe surface of a meat product is also considered to be a free liquid.Still further, if a liquid (such as brine) is injected into a meatproduct and thereafter exudes from the meat product, the liquid thatexudes from the meat product is likewise considered to be free liquid,even though the liquid is not a natural juice within the meat product.

[0022] As used herein, the term “film” is used in a generic sense toinclude plastic web, regardless of whether it is film or sheet.Preferably, films of and used in the present invention have a thicknessof 0.25 mm or less. As used herein, the term “package” refers topackaging materials used in the packaging of a product.

[0023] Preferably, the film according to the present invention comprisesa total of from 3 to 20 layers; more preferably, from 4 to 12 layers;and still more preferably, from 5 to 9 layers. The multilayer film ofthe present invention can have any total thickness desired, so long asthe film provides the desired properties for the particular packagingoperation in which the film is used, especially desired drop testresults.

[0024] As used herein, the phrases “seal layer”, “sealing layer”, “heatseal layer”, and “sealant layer”, refer to an outer layer, or layers,involved in the sealing of the film to itself, another layer of the sameor another film, and/or another article which is not a film. Although itshould also be recognized that up to the outer 3 mils of a film can beinvolved in the sealing of the film to itself or another layer, thephrase “seal layer,” and the like, refer herein only to the outerlayer(s) which is to be heat-sealed to itself, another film, etc. Anyinner layers which contribute to the sealing performance of the film areherein designated as “seal-assist” layers. With respect to packageshaving only fin-type seals, as opposed to lap-type seals, the phrase“sealant layer” generally refers to the inside layer of a package, theinside layer being an outer layer which frequently also serves as a foodcontact layer in the packaging of foods. However, in a multilayer film,the composition of the other layers (within 3 mils of the insidesurface) can also affect sealability and seal strength.

[0025] Sealant layers employed in the packaging arts have included thegenus of thermoplastic polymer, which includes thermoplastic polyolefin,polyamide, polyester, polyvinyl chloride, and ionomer. Preferredpolymers for the sealant layer include homogeneous ethylene/alpha-olefincopolymer, ethylene/vinyl acetate copolymer, and ionomer.

[0026] As used herein, the term “heat-seal,” and the phrase“heat-sealing,” refer to any seal of a first region of a film surface toa second region of a film surface, wherein the seal is formed by heatingthe regions to at least their respective seal initiation temperatures.The heating can be performed by any one or more of a wide variety ofmanners, such as using a heated bar, hot wire, hot air, infraredradiation, ultrasonic sealing, etc. Heat-sealing is the process ofjoining two or more thermoplastic films or sheets by heating areas incontact with each other to the temperature at which fusion occurs,usually aided by pressure. Heat-sealing is inclusive of thermal sealing,melt-bead sealing, impulse sealing, dielectric sealing, and ultrasonicsealing.

[0027] As used herein, the term “barrier,” and the phrase “barrierlayer,” as applied to films and/or layers, is used with reference to theability of a film or layer to serve as a barrier to one or more gases.In the packaging art, oxygen (i e., gaseous O₂) barrier layers haveincluded, for example, ethylene/vinyl alcohol copolymer, polyvinylidenechloride (PVDC), polyalkylene carbonate, polyamide, polyethylenenaphthalate, polyester, polyacrylonitrile, etc., as known to those ofskill in the art. However, in the present invention the O₂-barrier layerpreferably comprises either EVOH or polyvinylidene chloride, the PVDCcomprising a thermal stabilizer (i.e., HCl scavenger, e.g., epoxidizedsoybean oil) and a lubricating processing aid, which, for example,comprises one or more acrylates.

[0028] As used herein, the phrases “abuse layer”, as well as the phrase“puncture-resistant layer”, refer to any layer which serves to resistabrasion, puncture, and other potential causes of reduction of packageintegrity, as well as potential causes of reduction of packageappearance quality. As used herein, the phrase “skin layer” refers to anoutside layer of a multilayer film in packaging a product, this skinlayer being subject to abuse.

[0029] As used herein, the term “core”, and the phrase “core layer”, asapplied to multilayer films, refer to any internal layer whichpreferably has a function other than serving as an adhesive orcompatibilizer for adhering two layers to one another. Usually, the corelayer or layers provide the multilayer film with a desired level ofstrength, i.e., modulus, and/or optics, and/or added abuse resistance,and/or specific impermeability.

[0030] As used herein, the phrase “tie layer” refers to any internallayer having the primary purpose of adhering two layers to one another.In one preferred embodiment, tie layers can comprise any polymer havinga polar group grafted thereon, so that the polymer is capable ofcovalent bonding to polar polymers such as polyamide and ethylene/vinylalcohol copolymer. Preferred polymers for use in tie layers include, butare not restricted to, ethylene/unsaturated acid copolymer,ethylene/unsaturated ester copolymer, anhydride-grafted polyolefin,polyurethane, and mixtures thereof.

[0031] As used herein, the phrase “bulk layer” refers to any layer of afilm which is present for the purpose of increasing theabuse-resistance, toughness, modulus, etc., of a multilayer film. Bulklayers generally comprise polymers which are inexpensive relative toother polymers in the film.

[0032] As used herein, the phrases “food-contact layer” and“meat-contact layer”, refer to a layer of a multilayer film which is indirect contact with the food/meat in the package comprising the film.The food-contact/meat-contact layer is an outer layer of the multilayerfilm, in the sense that the food-contact/meat-contact layer is in directcontact with the meat product within the package. Thefood-contact/meat-contact layer is an inside layer in the sense thatwith respect to the packaged food product/meat product, thefood-contact/meat-contact layer is the inside layer (i.e., innermostlayer) of the package, this inside layer being in direct contact withthe food/meat.

[0033] As used herein, the phrase “food-contact surface” and“meat-contact surface” refers to an outer surface of a food-contactlayer/meat-contact layer, this outer surface being in direct contactwith the food/meat within the package.

[0034] As used herein, “EVOH” refers to ethylene/vinyl alcoholcopolymer, i.e, polymerized ethylene vinyl alcohol. EVOH includessaponified or hydrolyzed ethylene/vinyl acetate copolymers, and refersto a vinyl alcohol copolymer having an ethylene comonomer, and preparedby, for example, hydrolysis of vinyl acetate copolymers, or by chemicalreactions with polyvinyl alcohol. The degree of hydrolysis is preferablyat least 50%, and more preferably, at least 85%. Preferably, the EVOHcomprises from about 28 to about 48 mole % ethylene, more preferably,from about 32 to about 44 mole % ethylene, and even more preferably,from about 38 to about 44 mole % ethylene.

[0035] As used herein, the term “oriented” refers to apolymer-containing material which has been stretched at an elevatedtemperature (the orientation temperature), followed by being “set” inthe stretched configuration by cooling the material while substantiallyretaining the stretched dimensions. Upon subsequently heatingunrestrained, unannealed, oriented polymer-containing material to itsorientation temperature, heat shrinkage is produced almost to theoriginal unstretched, i.e., pre-oriented dimensions. More particularly,the term “oriented”, as used herein, refers to oriented films, whereinthe orientation can be produced in one or more of a variety of manners.

[0036] As used herein, the phrase “orientation ratio” refers to themultiplication product of the extent to which the plastic film materialis expanded in several directions, usually two directions perpendicularto one another. Expansion in the machine direction is herein referred toas “drawing”, whereas expansion in the transverse direction is hereinreferred to as “stretching”. For films extruded through an annular die,stretching is usually obtained by “blowing” the film to produce abubble. For such films, drawing is usually obtained by passing the filmthrough two sets of powered nip rolls, with the downstream set having ahigher surface speed than the upstream set, with the resulting drawratio being the surface speed of the downstream set of nip rolls dividedby the surface speed of the upstream set of nip rolls. The degree oforientation is also referred to as the orientation ratio, or sometimesas the “racking ratio”.

[0037] As used herein, the phrase “machine direction”, hereinabbreviated “MD”, refers to a direction “along the length” of the film,i.e., in the direction of the film as the film is formed duringextrusion and/or coating. As used herein, the phrase “transversedirection”, herein abbreviated “TD”, refers to a direction across thefilm, perpendicular to the machine or longitudinal direction.

[0038] As used herein, the phrases “heat-shrinkable,” “heat-shrink,” andthe like, refer to the tendency of a film, generally an oriented film,to shrink upon the application of heat, i.e., to contract upon beingheated, such that the size (area) of the film decreases while the filmis in an unrestrained state. Likewise, the tension of a heat-shrinkablefilm increases upon the application of heat if the film is restrainedfrom shrinking. As a corollary, the phrase “heat-contracted” refers to aheat-shrinkable film, or a portion thereof, which has been exposed toheat such that the film or portion thereof is in a heat-shrunken state,i.e., reduced in size (unrestrained) or under increased tension(restrained).

[0039] As used herein, the phrase “free shrink” refers to the percentdimensional change in a 10 cm×10 cm specimen of film, when subjected toselected heat (i.e., at a certain temperature), with the quantitativedetermination being carried out according to ASTM D 2732, as set forthin the 1990 Annual Book of ASTM Standards, Vol. 08.02, pp.368-371, whichis hereby incorporated, in its entirety, by reference thereto.

[0040] As used herein, the phrase “heat-shrinkable” is used withreference to all films which exhibit a total free shrink (i.e., L+T) ofat least 10 percent at 185° F. The multilayer film used in the presentinvention preferably has a total free shrink (i.e., L+T beforeshrinkage) of at least 40 percent at 185° F. Moreover, the filmpreferably has a free shrink of at least 15 percent at 185° F. in themachine direction, and at least 15 percent at 185° F. in the transversedirection. “Total free shrink” is determined by summing the percent freeshrink in the machine direction with the percentage of free shrink inthe transverse direction. For example, a film which exhibits, at 185°F., 30 percent free shrink in the transverse direction and 20 percentfree shrink in the machine direction, has a “total free shrink” at 185°F. of 50 percent.

[0041] The multilayer films of the invention can be annealed or heat-setto reduce the free shrink either slightly, substantially or completely.

[0042] As used herein, the term “monomer” refers to a relatively simplecompound, usually containing carbon and of low molecular weight, whichcan react to form a polymer by combining with itself or with othersimilar molecules or compounds.

[0043] As used herein, the term “comonomer” refers to a monomer which iscopolymerized with at least one different monomer in a copolymerizationreaction, the result of which is a copolymer.

[0044] As used herein, the term “polymer” refers to the product of apolymerization reaction, and is inclusive of homopolymers, copolymers,terpolymers, etc. A film layer can consist of a single polymer (with orwithout non-polymeric additives), or can have still additional polymerstogether therewith, i.e., blended therewith.

[0045] As used herein, the term “homopolymer” is used with reference toa polymer resulting from the polymerization of a single monomer, i.e, apolymer consisting essentially of a single type of mer, i.e., repeatingunit.

[0046] As used herein, the term “copolymer” refers to polymers formed bythe polymerization reaction of at least two different monomers. Forexample, the term “copolymer” includes the copolymerization reactionproduct of ethylene and an alpha-olefin, such as 1-hexene. However, theterm “copolymer” is also inclusive of, for example, the copolymerizationof a mixture of ethylene, propylene, 1-hexene, and 1-octene. The termcopolymer is also inclusive of polymers produced by reaction, such asgraft copolymer, block copolymer, and random copolymer.

[0047] As used herein, the term “polymerization” is inclusive ofhomopolymerizations, copolymerizations, terpolymerizations, etc, andincludes all types of copolymerizations such as random, graft, block,etc. Polymers in the films used in accordance with the presentinvention, can be prepared in accordance with any suitablepolymerization process, including slurry polymerization, gas phasepolymerization, and high pressure polymerization processes.

[0048] As used herein, the term “copolymerization” refers to thesimultaneous polymerization of two or more monomers to result in acopolymer. As used herein, a copolymer identified in terms of aplurality of monomers, e.g., “propylene/ethylene copolymer”, refers to acopolymer in which either monomer may copolymerize in a higher weight ormolar percent than the other monomer or monomers. However, the firstlisted monomer preferably polymerizes in a higher weight percent thanthe second listed monomer, and, for copolymers which are terpolymers,quadripolymers, etc., preferably the first monomer copolymerizes in ahigher weight percent than the second monomer, and the second monomercopolymerizes in a higher weight percent than the third monomer, etc.

[0049] For addition polymers, copolymers are identified, i.e., named, interms of the monomers from which the copolymers are produced. Forexample, the phrase “propylene/ethylene copolymer” refers to a copolymerproduced by the copolymerization of both propylene and ethylene, with orwithout additional comonomer(s). A copolymer comprises recurring “mers”derived from the monomers from which the copolymer is produced, e.g., apropylene/ethylene copolymer comprises propylene mer units and ethylenemer units.

[0050] As used herein, terminology employing a “/” with respect to thechemical identity of a copolymer (e.g., “an ethylene/alpha-olefincopolymer”), identifies the comonomers which are copolymerized toproduce the copolymer. As used herein, “ethylene alpha-olefin copolymer”is the equivalent of “ethylene/alpha-olefin copolymer.”

[0051] As used herein, the phrase “heterogeneous polymer” refers topolymerization reaction products of relatively wide variation inmolecular weight and relatively wide variation in compositiondistribution, i.e, typical polymers prepared, for example, usingconventional Ziegler-Natta catalysts. Heterogeneous polymers are usefulin various layers of the film used in the present invention. Althoughthere are a few exceptions (such as TAFMER™ linear homogeneousethylene/alpha-olefin copolymers produced by Mitsui PetrochemicalCorporation, using Ziegler-Natta catalysts), heterogeneous polymerstypically contain a relatively wide variety of chain lengths andcomonomer percentages.

[0052] As used herein, the phrase “homogeneous polymer” refers topolymerization reaction products of relatively narrow molecular weightdistribution and relatively narrow composition distribution. Homogeneouspolymers are useful in various layers of the multilayer film used in thepresent invention. Homogeneous polymers are structurally different fromheterogeneous polymers, in that homogeneous polymers exhibit arelatively even sequencing of comonomers within a chain, a mirroring ofsequence distribution in all chains, and a similarity of length of allchains, i.e., a narrower molecular weight distribution. Furthermore,homogeneous polymers are typically prepared using metallocene, or othersingle-site type catalysis, rather than using Ziegler Natta catalysts.

[0053] More particularly, homogeneous ethylene/alpha-olefin copolymersmay be characterized by one or more methods known to those of skill inthe art, such as molecular weight distribution (M_(w)/M_(n)),composition distribution breadth index (CDBI), and narrow melting pointrange and single melt point behavior. The molecular weight distribution(M_(w)/M_(n)), also known as polydispersity, may be determined by gelpermeation chromatography. The homogeneous ethylene/alpha-olefincopolymers useful in this invention generally have (M_(w)/M_(n)) of lessthan 2.7; preferably from about 1.9 to about 2 5; more preferably, fromabout 1.9 to about 2.3. The composition distribution breadth index(CDBI) of such homogeneous ethylene/alpha-olefin copolymers willgenerally be greater than about 70 percent. The CDBI is defined as theweight percent of the copolymer molecules having a comonomer contentwithin 50 percent (i.e., plus or minus 50%) of the median total molarcomonomer content. The CDBI of linear polyethylene, which does notcontain a comonomer, is defined to be 100%. The Composition DistributionBreadth Index (CDBI) is determined via the technique of TemperatureRising Elution Fractionation (TREF). CDBI determination clearlydistinguishes the homogeneous copolymers used in the present invention(narrow composition distribution as assessed by CDBI values generallyabove 70%) from VLDPEs available commercially which generally have abroad composition distribution as assessed by CDBI values generally lessthan 55%. The CDBI of a copolymer is readily calculated from dataobtained from techniques known in the art, such as, for example,temperature rising elution fractionation as described, for example, inWild et. al., J. Poly. Sci. Poly. Phys. Ed., Vol. 20, p 441 (1982).Preferably, the homogeneous ethylene/alpha-olefin copolymers have a CDBIgreater than about 70%, i.e., a CDBI of from about 70% to about 99%. Thehomogeneous ethylene/alpha-olefin copolymers in the multilayer films tobe used in the present invention also exhibit a relatively narrowmelting point range, in comparison with “heterogeneous copolymers”,i.e., polymers having a CDBI of less than 55%. Preferably, thehomogeneous ethylene/alpha-olefin copolymers exhibit an essentiallysingular melting point characteristic, with a peak melting point(T_(m)), as determined by Differential Scanning Colorimetry (DSC), offrom about 60° C. to about 105° C. Preferably the homogeneous copolymerhas a DSC peak T_(m) of from about 80° C. to about 100° C. As usedherein, the phrase “essentially single melting point” means that atleast about 80%, by weight, of the material corresponds to a singleT_(m) peak at a temperature within the range of from about 60° C. toabout 105° C., and essentially no substantial fraction of the materialhas a peak melting point in excess of about 115° C., as determined byDSC analysis. DSC measurements are made on a Perkin Elmer System 7Thermal Analysis System. Melting information reported are second meltingdata, i.e., the sample is heated at a programmed rate of 10° C./min. toa temperature below its critical range. The sample is then reheated (2ndmelting) at a programmed rate of 10° C./min. The presence of highermelting peaks is detrimental to film properties such as haze, andcompromises the chances for meaningful reduction in the seal initiationtemperature of the final film.

[0054] A homogeneous ethylene/alpha-olefin copolymer can be prepared bythe copolymerization of ethylene and any one or more alpha-olefins.Preferably, the alpha-olefin is a C₃-C₂₀ alpha-monoolefin, morepreferably, a C₄-C₁₂ alpha-monoolefin, still more preferably, a C₄-C₈alpha-monoolefin. Still more preferably, the alpha-olefin comprises atleast one member selected from the group consisting of butene-1,hexene-1, and octene-1, i.e., 1-butene, 1-hexene, and 1-octene,respectively. Most preferably, the alpha-olefin comprises octene-1,and/or a blend of hexene-l and butene-1

[0055] Processes for preparing and using homogeneous polymers aredisclosed in U.S. Pat. No. 5,206,075, U.S. Pat. No. 5,241,031, and PCTInternational Application WO 93/03093, each of which is herebyincorporated by reference thereto, in its entirety. Further detailsregarding the production and use of homogeneous ethylene/alpha-olefincopolymers are disclosed in PCT International Publication Number WO90/03414, and PCT International Publication Number WO 93/03093, both ofwhich designate Exxon Chemical Patents, Inc. as the Applicant, and bothof which are hereby incorporated by reference thereto, in theirrespective entireties.

[0056] Still another genus of homogeneous ethylene/alpha-olefincopolymers is disclosed in U.S. Pat. No. 5,272,236, to LAI, et. al., andU.S. Pat. No. 5,278,272, to LAI, et. al., both of which are herebyincorporated by reference thereto, in their respective entireties.

[0057] As used herein, the term “polyolefin” refers to any polymerizedolefin, which can be linear, branched, cyclic, aliphatic, aromatic,substituted, or unsubstituted. More specifically, included in the termpolyolefin are homopolymers of olefin, copolymers of olefin, copolymersof an olefin and an non-olefinic comonomer copolymerizable with theolefin, such as vinyl monomers, modified polymers thereof, and the like.Specific examples include polyethylene homopolymer, polypropylenehomopolymer, polybutene, ethylene/alpha-olefin copolymer,propylene/alpha-olefin copolymer, butene/alpha-olefin copolymer,ethylene/unsaturated ester copolymer, ethylene/unsaturated acidcopolymer. (especially ethyl acrylate copolymer, ethylene/butyl acrylatecopolymer, ethylene/methyl acrylate copolymer, ethylene/acrylic acidcopolymer, ethylene/methacrylic acid copolymer), modified polyolefinresin, ionomer resin, polymethylpentene, etc. Modified polyolefin resinis inclusive of modified polymer prepared by copolymerizing thehomopolymer of the olefin or copolymer thereof with an unsaturatedcarboxylic acid, e g., maleic acid, fumaric acid or the like, or aderivative thereof such as the anhydride, ester or metal salt or thelike. It could also be obtained by incorporating into the olefinhomopolymer or copolymer, an unsaturated carboxylic acid, e.g., maleicacid, fumaric acid or the like, or a derivative thereof such as theanhydride, ester or metal salt or the like.

[0058] As used herein, terms identifying polymers, such as “polyamide”,“polyester”, “polyurethane”, etc. are inclusive of not only polymerscomprising repeating units derived from monomers known to polymerize toform a polymer of the named type, but are also inclusive of comonomers,derivatives, etc. which can copolymerize with monomers known topolymerize to produce the named polymer. For example, the term“polyamide” encompasses both polymers comprising repeating units derivedfrom monomers, such as caprolactam, which polymerize to form apolyamide, as well as copolymers derived from the copolymerization ofcaprolactam with a comonomer which when polymerized alone does notresult in the formation of a polyamide. Furthermore, terms identifyingpolymers are also inclusive of mixtures, blends, etc of such polymerswith other polymers of a different type.

[0059] As used herein, the phrase “modified polymer”, as well as morespecific phrases such as “modified ethylene/vinyl acetate copolymer”,and “modified polyolefin” refer to such polymers having an anhydridefunctionality, as defined immediately above, grafted thereon and/orcopolymerized therewith and/or blended therewith. Preferably, suchmodified polymers have the anhydride functionality grafted on orpolymerized therewith, as opposed to merely blended therewith.

[0060] As used herein, the phrase “anhydride-containing polymer” and“anhydride-modified polymer”, refer to one or more of the following: (1)polymers obtained by copolymerizing an anhydride-containing monomer witha second, different monomer, and (2) anhydride grafted copolymers, and(3) a mixture of a polymer and an anhydride-containing compound.

[0061] As used herein, the phrase “ethylene alpha-olefin copolymer”, and“ethylene/alpha-olefin copolymer”, refer to such heterogeneous materialsas linear low density polyethylene (LLDPE), and very low and ultra lowdensity polyethylene (VLDPE and ULDPE), and homogeneous polymers such asmetallocene-catalyzed EXACT™ linear homogeneous ethylene/alpha olefincopolymer resins obtainable from the Exxon Chemical Company, of Baytown,Tex., and TAFMER™ linear homogeneous ethylene/alpha-olefin copolymerresins obtainable from the Mitsui Petrochemical Corporation. All thesematerials generally include copolymers of ethylene with one or morecomonomers selected from C₄ to C₁₀ alpha-olefin such as butene-1 (i.e.,1-butene), hexene-1, octene-1, etc in which the molecules of thecopolymers comprise long chains with relatively few side chain branchesor cross-linked structures. This molecular structure is to be contrastedwith conventional low or medium density polyethylenes which are morehighly branched than their respective counterparts. The heterogeneousethylene/alpha-olefin commonly known as LLDPE has a density usually inthe range of from about 0.91 grams per cubic centimeter to about 0.94grams per cubic centimeter. Other ethylene/alpha-olefin copolymers, suchas the long chain branched homogeneous ethylene/alpha-olefin copolymersavailable from The Dow Chemical Company, known as AFFINITY™ resins, arealso included as another type of homogeneous ethylene/alpha-olefincopolymer useful in the present invention.

[0062] The ethylene/alpha-olefin copolymer comprises a copolymerresulting from the copolymerization of from about 80 to about 99 weightpercent ethylene and from 1 to about 20 weight percent alpha-olefin.Preferably, the ethylene/alpha-olefin copolymer comprises a copolymerresulting from the copolymerization of from about 85 to about 95 weightpercent ethylene and from about 5 to about 15 weight percentalpha-olefin.

[0063] As used herein, the phrases “inner layer” and “internal layer”refer to any layer, of a multilayer film, having both of its principalsurfaces directly adhered to another layer of the film.

[0064] As used herein, the phrase “outer layer” refers to any layer offilm having less than two of its principal surfaces directly adhered toanother layer of the film. The phrase is inclusive of monolayer andmultilayer films. In multilayer films, there are two outer layers, eachof which has a principal surface adhered to only one other layer of themultilayer film. In monolayer films, there is only one layer, which, ofcourse, is an outer layer in that neither of its two principal surfacesare adhered to another layer of the film.

[0065] As used herein, the phrase “inside layer” refers to the outerlayer, of a multilayer film packaging a product, which is closest to theproduct, relative to the other layers of the multilayer film. “Insidelayer” also is used with reference to the innermost layer of a pluralityof concentrically arranged layers simultaneously coextruded through anannular die.

[0066] As used herein, the phrase “outside layer” refers to the outerlayer, of a multilayer film packaging a product, which is furthest fromthe product relative to the other layers of the multilayer film. Thephrase “outside layer” also is used with reference to the outermostlayer of a plurality of concentrically arranged layers coextrudedthrough an annular die.

[0067] As used herein, the term “adhered” is inclusive of films whichare directly adhered to one another using a heat-seal or other means, aswell as films which are adhered to one another using an adhesive whichis between the two films. As used herein, the phrase “directly adhered”,as applied to layers, is defined as adhesion of the subject layer to theobject layer, without a tie layer, adhesive, or other layertherebetween. In contrast, as used herein, the word “between”, asapplied to a layer expressed as being between two other specifiedlayers, includes both direct adherence of the subject layer between tothe two other layers it is between, as well as including a lack ofdirect adherence to either or both of the two other layers the subjectlayer is between, i.e., one or more additional layers can be imposedbetween the subject layer and one or more of the layers the subjectlayer is between.

[0068] As used herein, the term “extrusion” is used with reference tothe process of forming continuous shapes by forcing a molten plasticmaterial through a die, followed by cooling or chemical hardening.Immediately prior to extrusion through the die, the relativelyhigh-viscosity polymeric material is fed into a rotating screw ofvariable pitch, i.e., an extruder, which forces the polymeric materialthrough the die.

[0069] As used herein, the term “coextrusion” refers to the process ofextruding two or more materials through a single die with two or moreorifices arranged so that the extrudates merge and weld together into alaminar structure before chilling, i.e., quenching. Coextrusion can beemployed in film blowing, free film extrusion, and extrusion coatingprocesses.

[0070] At least a portion of the multilayer film of the presentinvention is preferably irradiated to induce crosslinking. In theirradiation process, the film is subjected to one or more energeticradiation treatments, such as corona discharge, plasma, flame,ultraviolet, X-ray, gamma ray, beta ray, and high energy electrontreatment, each of which induces cross-linking between molecules of theirradiated material. The irradiation of polymeric films is disclosed inU.S. Pat. No. 4,064,296, to BORNSTEIN, et. al, which is herebyincorporated in its entirety, by reference thereto BORNSTEIN, et. al.discloses the use of ionizing radiation for crosslinking the polymerpresent in the film.

[0071] To produce crosslinking, a suitable radiation dosage of highenergy electrons is employed, preferably using an electron accelerator,with a dosage level being determined by standard dosimetry methods.Other accelerators such as a Van de Graaf or resonating transformer maybe used. The radiation is not limited to electrons from an acceleratorsince any ionizing radiation may be used. The ionizing radiation can beused to crosslink the polymers in the film. Preferably, the film isirradiated at a level of from about 30 kGy to about 207 kGy, morepreferably from about 30 kGy to about 140 kGy. As can be seen from thedescriptions of preferred films for use in the present invention, themost preferred amount of radiation is dependent upon the film and itsend use.

[0072] As used herein, the phrases “corona treatment” and “coronadischarge treatment” refer to subjecting the surfaces of thermoplasticmaterials, such as polyolefins, to corona discharge, i.e., theionization of a gas such as air in close proximity to a film surface,the ionization initiated by a high voltage passed through a nearbyelectrode, and causing oxidation and other changes to the film surface,such as surface roughness.

[0073] Corona treatment of polymeric materials is disclosed in U.S. Pat.No. 4,120,716, to BONET, issued Oct. 17, 1978, herein incorporated inits entirety by reference thereto BONET discloses improved adherencecharacteristics of the surface of polyethylene by corona treatment, tooxidize the polyethylene surface. U.S. Pat. No. 4,879,430, to HOFFMAN,also hereby incorporated in its entirety by reference thereto, disclosesthe use of corona discharge for the treatment of plastic webs for use inmeat cook-in packaging, with the corona treatment of the inside surfaceof the web to increase the adhesion of the meat to the adhesion of themeat to the proteinaceous material. The films of this invention can becorona-treated in a preferred embodiment.

[0074] Various combinations of layers can be used in the formation ofthe multilayer films for use in the present invention. Only 4-, 6-, and7-layer preferred embodiments are provided here as illustrations. Themultilayer films useful in the present invention can also compriseadditional layers or fewer layers. Thus, modifications and variationsmay be utilized without departing from the principles and scope of theinvention, as those skilled in the art will readily understand.

[0075] Preferably, the film is produced by casting an annular tape whichis thereafter oriented at least 2:1 in at least 1 direction; morepreferably, from about 2:1 to about 10:1 in at least one direction;still more preferably, at least 2.5:1 to 5:1 in at least one direction.

[0076]FIG. 1 is a schematic of a preferred end seal bag 10, in alay-flat position, this bag being in accord with the present invention;FIG. 2 is a cross-sectional view of bag 10 taken through section 2-2 ofFIG. 1. Viewing FIGS. 1 and 2 together, bag 10 comprises bag film 11,top edge 12 defining an open top, first bag side edge 13, second bagside edge 14, bottom edge 15, and end seal 16.

[0077]FIGS. 3 and 4 illustrate side-seal bag 18. FIG. 3 illustrates aschematic of side seal bag 18, in a lay-flat view, FIG. 4 illustrates across-sectional view taken through section 4-4 of FIG. 3. With referenceto FIGS. 3 and 4 together, side seal bag 18 is comprised of bag film 19,top edge 20 defining an open top, bottom edge 21, first side seal 22,and second side seal 23.

[0078] In addition to the bag-type packaging articles illustrated inFIGS. 1-4 and described above, the packaging article can also be acasing made from a flexible packaging film, ie., a film tubing. Thecasing can be a seamless casing or a backseamed casing, the latter beinga casing having a seam running the length of the tubing. Backseamedcasings include both lap-seal backseamed casings as well as butt-sealedbackseamed casings, the latter utilizing a butt-seal tape which issealed to the casing film, as is known to those of skill in the art.Another type of packaging article which can be utilized is generallyreferred to as a “pouch,” which is generally made from two rectangularpieces of flexible packaging film of the same dimensions, which aresealed to one another along 3 edges, leaving the unsealed fourth edgesto form the open top, into which a product can be inserted.

[0079]FIG. 5 illustrates a schematic view of a first preferred processfor making films according to the present invention. As illustrated inFIG. 5, solid polymer beads (not illustrated) are fed to a plurality ofextruders 28 (for simplicity, only one extruder is illustrated). Insideextruders 28, the polymer beads are forwarded, melted, and degassed,following which the resulting bubble-free melt is forwarded into diehead 30, and extruded through an annular die, resulting in tubing 32which is preferably about 10 to 20 mils thick.

[0080] After cooling or quenching by water spray from cooling ring 34,tubing 32 is collapsed by pinch rolls 36, and is thereafter fed throughirradiation vault 38 surrounded by shielding 40, where tubing 32 isirradiated with high energy electrons (i.e., ionizing radiation) fromiron core transformer accelerator 42. Tubing 32 is guided throughirradiation vault 38 on rolls 44. Preferably, tubing 32 is irradiated toa level of from about 40 kGy to about 120 kGy.

[0081] After irradiation, irradiated tubing 46 is directed through pinchrolls 48, following which irradiated tubing 46 is slightly inflated,resulting in trapped bubble 50 However, at trapped bubble 50, the tubingis not significantly drawn longitudinally, as the surface speed of niprolls 52 are about the same speed as nip rolls 48. Furthermore,irradiated tubing 46 is inflated only enough to provide a substantiallycircular tubing without significant transverse orientation, i.e.,without stretching.

[0082] Slightly inflated, irradiated tubing 46 is passed through vacuumchamber 54, and thereafter forwarded through coating die 56. Annularcoating stream 58 is melt extruded from coating die 56 and coated ontoslightly inflated, irradiated tube 50, to form two-ply tubular film 60.Coating stream 58 preferably comprises an O₂-barrier layer, which doesnot pass through the ionizing radiation. Further details of theabove-described coating step are generally as set forth in U.S. Pat. No.4,278,738, to BRAX et. al., which is hereby incorporated by referencethereto, in its entirety.

[0083] After irradiation and coating, two-ply tubing film 60 is wound uponto windup roll 62. Thereafter, windup roll 62 is removed and installedas unwind roll 64, on a second stage in the process of making the tubingfilm as ultimately desired. Two-ply tubular film 60, from unwind roll64, is unwound and passed over guide roll 66, after which two-plytubular film 60 passes into hot water bath tank 68 containing hot water70. The now collapsed, irradiated, coated tubular film 60 is immersed inhot water 70 (preferably at a temperature of from about 185° F. to 210°F.) for a period of from about 10 to about 100 seconds, ie., for a timeperiod in order to bring the film up to the desired temperature forbiaxial orientation.

[0084] Thereafter, irradiated tubular film 60 is directed through niprolls 72, and bubble 74 is blown, thereby transversely stretchingtubular film 60. Furthermore, while being blown, i.e., transverselystretched, nip rolls 76 draw tubular film 60 in the longitudinaldirection, as nip rolls 76 have a surface speed higher than the surfacespeed of nip rolls 72. As a result of the transverse stretching andlongitudinal drawing, irradiated, coated biaxially-oriented blown tubingfilm 78 is produced, this blown tubing preferably having been bothstretched in a ratio of from about 1:1.5 to about 1:6, and drawn at aratio of from about 1:1.5 to about 1:6; more preferably, the stretchingand drawing are each performed a ratio of from about 1 2 to about 1:4.The result is a biaxial orientation of from about 1:2.25 to about 1:36,more preferably, from about 1:4 to about 1:16. While bubble 74 ismaintained between pinch rolls 72 and 76, blown tubing 78 is collapsedby rollers 80, and thereafter conveyed through pinch rolls 76 and acrossguide roll 82, and then rolled onto wind-up roll 84. Idler roll 86assures a good wind-up.

[0085] The invention is illustrated by the following examples, which areprovided for the purpose of representation, and are not to be construedas limiting the scope of the invention. Unless stated otherwise, allpercentages, parts, etc. are by weight

EXAMPLES 1-4

[0086] Four different ethylene-based heat-shrinkable, coextrudedmultilayer films were prepared by a process as schematically illustratedin FIG. 5 (described above). Each of the films was converted into aplurality of end-seal bags. For each of the four different bag types,some of the bags were sealed shut in the absence of any product beingplaced within the bag. For the remaining bags of each type, abrine-injected pork product was placed within the bag, with thebrine/meat juice blend, being on the surface of the meat product,contaminating the area to be the area to be sealed. The average sealstrengths of the bags were as follows. TABLE 1 Avg. Seal Strength ofAvg. Seal Strength of % Reduction in Seal Film Clean Bag Bag with BrineStrength Due to Brine Identity Seal (lb/in) Contamination (lb/in) onSeal Area 1 10.92 2.73 75.0 2 10.16 162 84.1 3 1148 3.50 69.5 4 9.45 33564.6

[0087] The results in Table 1 clearly establish that seal strength isgreatly reduced if the seal is made through brine in admixture with porkpurge. The clean bag seal strengths of from 9.45 to 11.48 lb/inestablishes that the chemical composition of the film was notresponsible for the low seal strength obtained in the presence of thecombination of brine and purge. Taken in total, the results indicatethat the combination of purge and brine was responsible for lowering theseal strength in an amount of from about 64.6% to about 84.1%.

EXAMPLE 5

[0088] A 7-layer, partially-irradiated, extrusion-coated, biaxiallyoriented, heat-shrinkable, O₂-barrier film was produced by a process asillustrated in FIG. 5, described above. In the process, a tapecontaining the first, second, and third layers was coextruded as asubstrate which was irradiated to a level of 71 kGy. Thereafter, thefourth, fifth, sixth, and seventh layers were extrusion coated onto theirradiated substrate. In this manner, the layer comprising PVDC-MA wasnot subjected to irradiation. The orientation of the resulting 22 milthick tape, i.e., to form the oriented, heat-shrinkable film, wascarried out by immersing the tape in hot water at 197° F., followed byimmediate immersion in hot water at 192° F., followed immediately byorientation. The tape was oriented 3.5× in the longitudinal direction,and 3.5× in the transverse direction. The resulting film had a thicknessof 2.2 mils. The film had a free shrink at 185° F. in the longitudinaldirection of 37 percent, and a free shrink at 185° F. in the transversedirection of 53 percent. The various layers of the tape had thefollowing composition and thickness: TABLE 2 Layer Layer ThicknessDesignation Layer Chemical Identity (mils) First Homogeneousethylene/alpha-olefin 5 copolymer #1 Second 90% homogeneousethylene/alpha-olefin #2 9 10% rubber Third EVA #1 1 Fourth PVDC/MA 2Fifth EMA 1 Sixth Homogeneous ethylene/alpha-olefin #2 2.5 SeventhHomogeneous ethylene/alpha-olefin #3 1.5

[0089] In Table 2 above, the identity of the resins used was as follows.First, “homogeneous ethylene/alpha-olefin #1” was AFFFINITY® PL 1280single site catalyzed, long chain branched ethylene/octene copolymerwhich had a density of 0.900 g/cc, and a melt index of 6.0 g/10 min,obtained from The Dow Chemical Company of Midland, Mich.

[0090] “Homogeneous ethylene/alpha-olefin #2” was DPF 1150.01single-site-catalyzed ethylene/octene copolymer which had a density of0.901 g/cc, and a melt index of 0.9 g/10 min., and was obtained from TheDow Chemical Company of Midland, Mich.

[0091] “Homogeneous ethylene/alpha-olefin #3” was AFFINITY® PL1850single-site-catalyzed, long chain branched, ethylene/octene copolymerwhich had a density of 0.902 g/cc, and a melt index of 3.0 g/10 min.,and was obtained from The Dow Chemical Company of Midland, Mich.

[0092] “Rubber” was BUNA EP-T-2370P ethylene/propylene/diene(5-ethyledene 2-norbornene) resin which had a density of 0.867 g/cc, amelt index of 2.0 g/10 min, and which was obtained from Bayer Inc.,Rubber Division, of Akron, Ohio.

[0093] “EVA #1” was LD-713.93 ethylene/vinyl acetate copolymer which hada vinyl acetate content of 15 percent, a density of 0.934 g/cc, and amelt index of 3.5 g/10 min., and which was obtained from the ExxonChemical Company of Baytown, Tex.

[0094] “PVDC/MA” was a blend of: (a) 96% XU32034.06 polyvinylidenechloride/methyl acrylate copolymer which contained 91.5% PVDC and 8.5%methyl acrylate, obtained from The Dow Chemical Company, of Midland,Mich.; (b) 2% PLAS CHEK® 775 epoxidized soy bean oil obtained from theBedford Chemical Division of Ferro Corporation, of Bedford, Mass.; and(c) 2% METABLEN® L-1000 butyl acrylate/methyl methacrylate/butylmethacrylate terpolymer having a density of 1.14 g/cc and obtained fromElf Atochem NA, Inc, of Philadelphia, Pa.; the blend of (a), (b), and(c) had a density of 1.69 g/cc.

[0095] “EMA” was EMAC SP 1305™ ethylene/methyl acrylate copolymer havinga density of 0.944 g/cc and a melt index of 2.0 g/l 0 min, and wasobtained from the Chevron Chemical Company of Houston, Tex.

EXAMPLE 6

[0096] Another 7-layer partially-irradiated, extrusion-coated, biaxiallyoriented, heat-shrinkable, O₂-barrier film was produced in by theprocess as illustrated in FIG. 5, and in accordance with the descriptionof Example 5, above. As is apparent from Table 3 below, the compositionof each of the film layers was the same, but the thicknesses of thelayers were different from the film of Example 5. The orientation of theresulting 17.6 mil thick tape, i.e., to form the oriented,heat-shrinkable film, was carried out by immersing the tape in hot waterat 197° F., followed by immediate immersion in hot water at 192° F.,followed immediately by orientation. The tape was oriented 2.8× in thelongitudinal direction, and 3.5× in the transverse direction. Theresulting film had a thickness of 2.2 mils. The film had a free shrinkat 185° F. in the longitudinal direction of 36 percent, and a freeshrink at 185° F. in the transverse direction of 48 percent. The variouslayers of the tape had the following composition and thickness: TABLE 3Layer Layer Thickness Designation Layer Chemical Identity (mils) FirstHomogeneous ethylene/alpha-olefin 4 copolymer #1 Second 90% homogeneousethylene/alpha-olefin #2 7.2 10% rubber Third EVA #1 0.8 Fourth PVDC/MA1.6 Fifth EMA 0.8 Sixth Homogeneous ethylene/alpha-olefin #2 2 SeventhHomogeneous ethylene/alpha-olefin #3 1.2

EXAMPLE 7

[0097] Another 7-layer partially-irradiated, extrusion-coated, biaxiallyoriented, heat-shrinkable, O₂-barrier film was produced in by theprocess as illustrated in FIG. 5, and in accordance with the descriptionof Example 6, above, except that the orientation of the resulting 17.6mil thick tape, i.e., to form the oriented, heat-shrinkable film, wascarried out by immersing the tape in hot water at 205° F., followed byimmediate immersion in hot water at 200° F., followed immediately byorientation. The tape was oriented 2.8× in the longitudinal direction,and 3.5× in the transverse direction. The resulting film had a thicknessof 2.2 mils. The film had a free shrink at 185° F. in the longitudinaldirection of 18 percent, and a free shrink at 185° F. in the transversedirection of 39 percent.

EXAMPLE 8

[0098] Another 7-layer partially-irradiated, extrusion-coated, biaxiallyoriented, heat-shrinkable, O₂-barrier film was produced in by theprocess as illustrated in FIG. 5, and in accordance with the descriptionof Example 6, above, except that the orientation of the resulting 17.6mil thick tape, ie., to form the oriented, heat-shrinkable film, wascarried out by immersing the tape in hot water at 202° F., followed byimmediate immersion in hot water at 192° F., followed immediately byorientation. The tape was oriented 2.8× in the longitudinal direction,and 3.5× in the transverse direction. The resulting film had a thicknessof 2.2 mils. The film had a free shrink at 185° F. in the longitudinaldirection of 36 percent, and a free shrink at 185° F. in the transversedirection of 53 percent.

EXAMPLE 9

[0099] Another 7-layer partially-irradiated, extrusion-coated, biaxiallyoriented, heat-shrinkable, O₂-barrier film was produced in by theprocess as illustrated in FIG. 5, and unless otherwise indicated, inaccordance with the description of Example 5, above. Table 4, below,sets forth the composition and relative thicknesses of each of thevarious layers of the film of this example. The orientation of theresulting 22 mil thick tape, i.e., to form the oriented, heat-shrinkablefilm, was carried out by immersing the tape in hot water at 197° F.,followed by immediate immersion in hot water at 191° F., followedimmediately by orientation. The tape was oriented 3.5× in thelongitudinal direction, and 3.5× in the transverse direction. Theresulting film had a thickness of 2.2 mils. The film had a free shrinkat 185° F. in the longitudinal direction of 37 percent, and a freeshrink at 185° F. in the transverse direction of 46 percent. The variouslayers of the tape had the following composition and thickness: TABLE 4Layer Layer Thickness Designation Layer Chemical Identity (mils) FirstHomogeneous ethylene/alpha-olefin 5 copolymer #1 Second 60% homogeneousethylene/alpha-olefin #2 9 30% LLDPE#1 10% rubber Third EVA #1 1 FourthPVDC/MA 2 Fifth EMA 1 Sixth Homogeneous ethylene/alpha-olefin #2 2.5Seventh Homogeneous ethylene/alpha-olefin #3 1.5

[0100] In Table 4 above, “LLDPE #1 was DOWLEX® 2045.03 ethylene/octenecopolymer which had a density of 0.920 g/cc, and a melt index of 1.1g/10 min., and was obtained from The Dow Chemical Company of Midland,Mich.

EXAMPLE 10

[0101] A 4-layer partially-irradiated, extrusion-coated, biaxiallyoriented, heat-shrinkable, O₂-barrier film was produced by a process asillustrated in FIG. 5, described above. In the process, a tapecontaining the first and second layers was coextruded as a substratewhich was irradiated to a level of 64 kGy. Thereafter, the third andfourth layers were extrusion coated onto the irradiated substrate. Inthis manner, the layer comprising PVDC-MA was not subjected toirradiation. The orientation of the resulting 25 mil thick tape, i.e.,to form the oriented, heat-shrinkable film, was carried out by immersingthe tape in a preheat water bath containing water at a temperature of210° F., followed by immediate immersion in a hot water bath containingwater also at 210° F., followed immediately by orientation. The tape wasoriented 3.5× in the longitudinal direction, and 3.5× in the transversedirection. The resulting film had a thickness of 2.32 mils. The film hada free shrink at 185° F. in the longitudinal direction of 21 percent,and a free shrink at 185° F. in the transverse direction of 30 percent.The various layers of the tape had the following composition andthickness: TABLE 5 Layer Layer Thickness Designation Layer ChemicalIdentity (mils) First 80% homogeneous ethylene/alpha-olefin 5 copolymer#1, and 20% LLDPE #2 Second 85% LLDPE#1 12 15% EBA Third PVDC/MA 2Fourth 90% EVA #2 6 10% HDPE

[0102] In Table 5 above, “LLDPE #2” was ESCORENE® LL3003.32ethylene/hexene copolymer which had a density of 0.9175 g/cc, and a meltindex of 3.2 g/10 min., and was obtained from the Exxon Chemical Companyof Baytown, Tex.

[0103] “EBA” was SP 1802 ethylene/butyl acrylate copolymer, having abutyl acrylate mer content of 18%, a density of 0 928 g/cc, and a meltindex of 0.5 g/10 min, and was obtained from the Chevron ChemicalCompany, of Houston, Tex.

[0104] “EVA #2” was ESCORENE® LD-318.92 ethylene/vinyl acetate copolymerwhich had a vinyl acetate content of 9 percent, a density of 0.930 g/cc,and a melt index of 2.0 g/10 min., and which was obtained from the ExxonChemical Company of Baytown, Tex.

[0105] “HDPE” was FORTIFLEX® T60-500-119 high density polyethylene,having a density of 0.961 g/cc, and a melt index of 6.2 g/10 min., andwhich was obtained from Solvay Polymers, Inc., of Houston, Tex.

EXAMPLE 11

[0106] A 7-layer partially-irradiated, extrusion-coated, biaxiallyoriented, heat-shrinkable, O₂-barrier film was produced by a process asillustrated in FIG. 5, described above. In the process, a tapecontaining the first, second, and third layers was coextruded as asubstrate which was irradiated to a level of 71 kGy. Thereafter, thefourth, fifth, sixth, and seventh layers were extrusion-coated onto theirradiated substrate. In this manner, the layer comprising PVDC-MA wasnot subjected to irradiation. The orientation of the resulting 22.2 milthick tape, i e., to form the oriented, heat-shrinkable film, wascarried out by immersing the tape in hot water at 197° F., followed byimmediate immersion in hot water at 192° F., followed immediately byorientation. The tape was oriented 3.6× in the longitudinal direction,and 3.55× in the transverse direction. The resulting film had athickness of 2.2 mils. The film had a free shrink at 185° F. in thelongitudinal direction of 32 percent, and a free shrink at 185° F. inthe transverse direction of 43 percent. The various layers of the tapehad the following composition and thickness. TABLE 6 Layer LayerThickness Designation Layer Chemical Identity (mils) First 80%homogeneous ethylene/alpha-olefin 4.9 copolymer #1, and 20% LLDPE #2Second 60% homogeneous ethylene/alpha-olefin #2 9.0 30% LLDPE#1 10%rubber Third EVA #1 1 0 Fourth PVDC/MA 1.9 Fifth EMA 1.0 SixthHomogeneous ethylene/alpha-olefin #2 2.6 Seventh 85% homogeneousethylene/alpha-olefin #3, 1.8 and 15% LLDPE #1

EXAMPLE 12 Comparative

[0107] A 6-layer partially-irradiated, extrusion-coated, biaxiallyoriented, heat-shrinkable, O₂-barrier film was produced by a process asillustrated in FIG. 5, described above. In the process, a tapecontaining the first and second layers was coextruded as a substratewhich was irradiated to a level of 64 kGy. Thereafter, the third,fourth, fifth, and sixth layers were extrusion-coated onto theirradiated substrate. In this manner, the layer comprising PVDC-MA wasnot subjected to irradiation. The orientation of the resulting 21.1 milthick tape, i.e., to form the oriented, heat-shrinkable film, wascarried out by immersing the tape in hot water at 193° F., followed byimmediate immersion in hot water at 180° F., followed immediately byorientation. The tape was oriented 3.2× in the longitudinal direction,and 3.7× in the transverse direction. The resulting film had a thicknessof 1.8 mils. The film had a free shrink at 185° F. in the longitudinaldirection of 48 percent, and a free shrink at 185° F. in the transversedirection of 60 percent. The various layers of the tape had thefollowing composition and thickness: TABLE 7 Layer Layer ThicknessDesignation Layer Chemical Identity (mils) First Homogeneousethylene/alpha-olefin copolymer 5 #1 Second EVA #1 8.4 Third PVDC/MA 2.2Fourth EMA 1.0 Fifth Homogeneous ethylene/alpha-olefin #4 3.0 Sixth 85%homogeneous ethylene/alpha-olefin #4, 1.5 and 2% Antiblock Masterbatch

[0108] In Table 7 above, “homogeneous ethylene/alpha-olefin #4” wasAFFINITY® PF1140 single-site-catalyzed, long chain branched,ethylene/octene copolymer which had a density of 0. 8965 g/cc, and amelt index of 1.6 g/10 min., and was obtained from The Dow ChemicalCompany of Midland, Mich.

[0109] “Antiblock Masterbatch” was L-7118-AB antiblock masterbatch inwhich 20% talc was present in an AFFINITY® ethylene/alpha-olefincopolymer carrier, obtained from Bayshore Industrial of LaPorte, Tex.;the masterbatch had a density of 1.039 and a melt index of 5.5 g/10 min.

EXAMPLE 13 Comparative

[0110] A 7-layer partially-irradiated, extrusion-coated, biaxiallyoriented, heat-shrinkable, O₂-barrier film was produced by a process asillustrated in FIG. 5, described above. In the process, a tapecontaining the first, second, and third layers was coextruded as asubstrate which was irradiated to a level of 50 kGy. Thereafter, thefourth, fifth, sixth, and seventh layers were extrusion-coated onto theirradiated substrate. In this manner, the layer comprising PVDC-MA wasnot subjected to irradiation. The orientation of the resulting 23.8 milthick tape, i.e., to form the oriented, heat-shrinkable film, wascarried out by immersing the tape in hot water at 205° F., followed byimmediate immersion in hot water at 195° F., followed immediately byorientation. The tape was oriented 3.5× in the longitudinal direction,and 4× in the transverse direction. The resulting film had a thicknessof 1.93 mils. The film had a free shrink at 185° F. in the longitudinaldirection of 31 percent, and a free shrink at 185° F. in the transversedirection of 45 percent. The various layers of the tape had thefollowing composition and thickness. TABLE 8 Layer Layer ThicknessDesignation Layer Chemical Identity (mils) First 80% homogeneousethylene/alpha-olefin 5.5 copolymer #1, and 20% LLDPE #2 Second EVA #39.1 Third EVA #3 1 0 Fourth PVDC/MA 2.2 Fifth EVA #2 0.8 Sixth EVA#2 3.9Seventh 90% EVA #2, and 1.3 10% HDPE

[0111] In Table 8 above, “EVA #3 was ESCORENE® LD 720.92 ethylene/vinylacetate copolymer which had a vinyl acetate content of 19 percent, adensity of 0.940 g/cc, and a melt index of 1.5 g/10 min., and which wasobtained from the Exxon Chemical Company of Baytown, Tex.

The “Standard Drop Test”

[0112] The Standard Drop Test was conducted as follows. First, bonelesspork sirloin pieces were injected with a brine-based injection solution.The brine-based injection solution contained about 5 percent sodiumchloride and about 1.1 percent phosphate. The boneless pork sirloinpieces were injected with the brine solution in an amount of about 11percent, based on the weight of the boneless sirloin pieces.

[0113] About 4½ pounds of injected pork sirloin pieces were then placedin a test bag (preferably, an end-seal bag) having a lay-flat width offrom about 8 to 9½ inches, and a length of about 18 inches. The sealarea of the bag was kept free of contamination by loading the meat intothe bag using a loading horn. Then, the seal area of the bag (i.e., aportion of the inside surface of the bag through which the seal was tobe made) was intentionally contaminated from about 5 to 6 milliliters ofa brine/purge seal contamination solution which was evenly dispersedonto the inside surface of the bag, in the area to be sealed.

[0114] The brine/purge seal contamination solution was prepared asfollows: 500 milliliters of the brine solution, which was the same asthe injection solution discussed above, as mixed with 500 milliliters ofpork purge (i.e., blood) and 100 g of lean pork muscle. This mixture wasthen blended until liquefied, and was chilled to a temperature of fromabout 32° to 45° F. for at least 1 hour prior to use.

[0115] After the brine/purge seal contamination solution was applied tothe seal area of the bag, the bag was heat sealed using a Cryovac®8600-B18 rotary chamber vacuum packaging machine. While in the Cryovac®8600-B18 rotary chamber vacuum packaging machine, the atmosphere withinthe bag was evacuated to a level of about 2-3 torr, and while the bagwas evacuated, it was closed around the product by heat sealing, theseal being made through that portion of the bag to which the brine/purgeseal contamination solution had been applied. The sealing parameterswere as follows: seal voltage: 76 amps; seal time: 0 5 seconds; machinespeed: 30 packages per minute. The seal was made within about 4 inchesof the injected pork sirloin pieces. After sealing, the resultingpackage was shrunk in a Cryovac® BFT6570 E shrink tunnel which operatedwith a water temperature of 195° F. and a belt speed of 55 ft/min.

[0116] Five of the resulting packages were placed in a 15 inches wide,by 23½ inches long by 9 inches deep, with the box material (corrugatedpaper board) being about ⅛ inch thick. The box containing the 5 packageswas then dropped from a height of 34″ onto a level, flat, hard surface,so that the bottom surface of the box lands flat on the hard surface.After dropping, the five packages were removed from the box, inflatedwith air, and submerged in water to determine if the seal made from theCryovac® 8600 B-18 packaging machine had failed, i.e., whether the sealwas leaking. Any air bubbles which came from this seal indicated a leak.

[0117] A total of 50 replications were conducted in order to establishthe performance criteria, i.e., the failure rate, which was reported interms of the percent of the bags which exhibited leaking at the seal. Inconducting the replications, no box was used (i.e., dropped) more thanthree times. Moreover, the sirloin pieces were used no more than 5times, i.e., no more than 5 replications. The sirloin pieces weremaintained at a temperature of from about 32° F. to 45° F. Between eachreplication the sirloin pieces were submerged in the brine solution fora minimum of 5 minutes before repackaging. The temperature of the brinesolution was maintained between 32° F. and 45° F.

Results of Standard Drop Test for Films of Examples 5 through 13

[0118] TABLE 9 Standard Drop Test Film of Example No. (% leakers)  5 36 6 34  7 36  8 26  9 32 10 36 11 30 12 (Comparative) 86 13 (Comparative)66

[0119] The results set forth in Table 9, above, show that the films ofExamples 5-11, when used in a Standard Drop Test, exhibited a percentleaker rate of from 26-36 percent. In contrast, the films of Examples 12and 13, both of which are comparative examples, exhibited a percentleaker rate of 86 percent and 66 percent, respectively.

[0120] It is not completely understood why the films of Examples 12 and13 did not perform as well in the Standard Drop Test as did the films ofExamples 5-11. However, it is believed that if the film shrinks in theshrink tunnel so that the seal (made through the brine-containingcontamination) is forced too tightly against the meat product, theweakness of this seal will cause a higher percentage of such bags tofail during the Standard Drop Test. The film of Example 12 (Comparative)had a significantly higher free shrink and shrink tension in thedirection perpendicular to the seal made through the contamination.Factors also believed to affect film performance in the Standard DropTest include seal layer composition (homogeneous ethylene/alpha-olefincopolymer appeared to perform better), film thickness (thicker filmsappeared to perform better), film free shrink and shrink tension in thedirection perpendicular to the seal made through the contamination (lowfree shrink and shrink tension appeared to perform better), amount andtype of contamination in the area to be sealed (less contamination isbetter), type of meat product (including size, shape, meat species,etc), and presence or absence of bone in the meat product.

[0121] In addition to the use of bags for carrying out the process ofthe present invention 9 and making the packaged product of the presentinvention), the multilayer film can be a tubular casing, preferably ashirrable casing. Preferably, the casing is used for the packaging offood products, especially boneless meat products and processed meatproducts. Among the types of meat which can be packaged in the films andpackages according to the present invention are poultry, pork, beef,sausage, lamb, goat, horse, and fish. Preferably, the casing of thepresent invention is used in the packaging of pork, poultry, beef, andsausage products.

[0122] The polymer components used to fabricate multilayer filmsaccording to the present invention may also contain appropriate amountsof other additives normally included in such compositions. These includeslip agents such as talc, antioxidants, fillers, dyes, pigments anddyes, radiation stabilizers, antistatic agents, elastomers, and the likeadditives known to those of skill in the art of packaging films.

[0123] All ranges within all of the above-disclosed ranges are expresslyincluded within this specification. Moreover, layers which are adjacentor directly adhered to one another are preferably of differing chemicalcomposition, especially differing polymeric composition. All referenceto ASTM tests are to the most recent, currently approved and publishedversion of the ASTM test identified, as of the priority filing date ofthis application.

[0124] Although the present invention has been described in connectionwith the preferred embodiments, it is to be understood thatmodifications and variations may be utilized without departing from theprinciples and scope of the invention, as those skilled in the art willreadily understand. Accordingly, such modifications may be practicedwithin the scope of the following claims.

What is claimed is:
 1. A packaged product comprising (A) a boneless foodproduct comprising at least one member selected from the groupconsisting of meat and cheese, the food product having an added liquidthereon; (B) a film article which is both surrounding and in contactwith both the food product and the added liquid, wherein the packagedproduct exhibits a Standard Drop Test failure rate of less than 60percent.
 2. The packaged product according to claim 1 , wherein the filmarticle comprises a heat-shrinkable film.
 3. The packaged productaccording to claim 1 , wherein the packaged product exhibits a StandardDrop Test failure rate of less than 50 percent.
 4. The packaged productaccording to claim 3 , wherein the packaged product exhibits a StandardDrop Test failure rate of less than 40 percent.
 5. The packaged productaccording to claim 1 , wherein the food product comprises meat.
 6. Thepackaged product according to claim 5 , wherein the meat productcomprises at least one member selected from the group consisting of porkand beef.
 7. The packaged product according to claim 6 , wherein themeat product comprises brine-injected pork.
 8. The packaged productaccording to claim 1 , wherein the added liquid comprises brine.
 9. Thepackaged product according to claim 8 , wherein the brine is present inan amount of from about 1 percent to 30 percent, based on the weight ofthe product.
 10. The packaged product according to claim 1 , wherein thefilm article comprises a multilayer film having a seal layer whichcomprises a homogeneous ethylene/alpha-olefin copolymer.
 11. Thepackaged product according to claim 1 , wherein the film articlecomprises a multilayer film having a thickness of from about 1.5 to 3mils.
 12. The packaged product according to claim 1 , wherein the filmarticle comprises a multilayer film having a free shrink of from about15 to 60 percent in at least one direction.
 13. The packaged productaccording to claim 1 , wherein the film article comprises a multilayerfilm having a shrink tension of from about 50 to 350 psi in a firstdirection, and from about 300 to 1000 psi in a second direction.
 14. Thepackaged product according to claim 1 , wherein the packaging articlecomprises a multilayer film having an inside layer comprising at leastone member selected from the group consisting of polyolefin, polyamide,polyester, polyvinyl chloride, and ionomer.
 15. A packaging processcomprising: (A) making a packaging article comprising at least onemember selected from the group consisting of a bag, a pouch, and acasing, the article having an open top; (B) placing into the packagingarticle a boneless food product having added liquid thereon, theboneless food product depositing liquid contamination onto a region ofan inside surface of the packaging article which is to be sealed afterthe boneless food product is placed into the packaging article, theliquid contamination comprising the added liquid; and (C) heat sealingacross the open top of the packaging article after the boneless foodproduct has been placed therein, the heat-sealing being carried outthrough the liquid contamination deposited onto the inside surface ofthe packaging article, whereby a packaged product is formed; and whereinthe packaged product exhibits a Standard Drop Test failure rate of lessthan 60 percent
 16. The process according to claim 15 , wherein theprocess further comprises evacuating atmosphere from within thepackaging article after the boneless food product is placed into thepackaging article but before the heat sealing across the open top of thepackaging article
 17. The process according to claim 15 , wherein theboneless food product comprises meat, and wherein brine is injected intothe meat before the meat is placed into the packaging article
 18. Theprocess according to claim 15 , wherein the packaging article comprisesa heat shrinkable film, and the process further comprises heat shrinkingthe packaging article after heat sealing across the open top of thepackaging article.
 19. The process according to claim 18 , wherein thepackaging article is an end-seal bag, and the heat-shrinkable film has afree shrink at 185° F. of from about 15 to about 60 percent in a machinedirection, and a free shrink at 185° F. of from about 15 to about 60percent in a transverse direction.
 20. The process according to claim 18, wherein the packaging article is an end-seal bag, and theheat-shrinkable film has a shrink tension at 185° F. in a machinedirection of from about 50 to about 350 psi, and a shrink tension at185° F. in a transverse direction of from about 310 to about 1000 psi,and wherein the shrink tension in the transverse direction is at least120 of the shrink tension in the machine direction.
 21. The processaccording to claim 15 , wherein the article comprises at least onemember selected from the group consisting of end-seal bag, side-sealbag, casing, and pouch, with the first direction being parallel to alength of the packaging article, and the second direction beingperpendicular to the length of the packaging article.
 22. The processaccording to claim 15 , wherein the boneless food product comprises atleast one member selected from the group consisting of meat and cheese.23. The process according to claim 15 , wherein the boneless foodproduct comprises brine-injected meat.